<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
         .outerDiv {
        width: 500px;
        height: 300px;
        border: 1px solid green;
        background-color: rgb(230, 224, 224);
        }
        .innerDiv{
            width: 100px;
            height: 100px;
            border: 1px solid blue;
            float: right;
        }
        .d1{
            background-color: greenyellow;
            
        }
        .d2{
            background-color: rgb(79, 230, 124);
                
        }
        .d3{
            background-color: rgb(26, 165, 208);
        }
    </style>
</head>
<body>
    <div class="outerDiv">
        <div class="innerDiv d1">框1</div>
        <div class="innerDiv d2">框2</div>
        <div class="innerDiv d3">框3</div>
    </div>
</body>
</html>